(19)
(11) EP 0 434 669 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
24.07.1991 Bulletin 1991/30

(43) Date of publication A2:
26.06.1991 Bulletin 1991/26

(21) Application number: 91103347.0

(22) Date of filing: 26.09.1985
(51) International Patent Classification (IPC)5: H01F 1/24
(84) Designated Contracting States:
DE FR GB SE

(30) Priority: 29.09.1984 JP 204870/84
27.12.1984 JP 274096/84

(62) Application number of the earlier application in accordance with Art. 76 EPC:
85306848.4 / 0177276

(71) Applicant: KABUSHIKI KAISHA TOSHIBA
Kawasaki-shi, Kanagawa-ken 210 (JP)

(72) Inventors:
  • Ochiai, Kumi, c/o Patent Division
    Minato-ku, Tokyo 105 (JP)
  • Horie, Hiromichi, c/o Patent Division
    Minato-ku, Tokyo 105 (JP)
  • Arima, Itsuo, c/o Patent Division
    Minato-ku, Tokyo 105 (JP)
  • Morita, Mikio, c/o Patent Division
    Minato-ku, Tokyo 105 (JP)

(74) Representative: Freed, Arthur Woolf et al
MARKS & CLERK, 57-60 Lincoln's Inn Fields
London WC2A 3LS
London WC2A 3LS (GB)


(56) References cited: : 
   
       


    (54) Method of making a coated magnetic powder and a compressed magnetic powder core


    (57) A compressed magnetic powder core comprising a compressed body of a magnetic powder and electrically insulating material separating the magnetic powder particles, characterized in that the magnetic powder has an average particle size of 10 to 300 µm, and the insulating material covers each of the particles of said magnetic powder and comprises a continuous insulating film having a thickness of 10 µm or less and comprising a metal alkoxide or a decomposition product thereof.






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